scholarly journals Laboratory tests results of a measuring station for plate bearing tests of road structures

2021 ◽  
pp. 49-55
Author(s):  
Ivan Shuliak ◽  
◽  
Serhii Sukhonosov ◽  
Oleksand Chechuha ◽  
◽  
...  
Keyword(s):  
Laboratory Tests ◽  
Absolute Error ◽  
Regulatory Requirements ◽  
Measuring Station ◽  
Multiple Loads ◽  
Special Software ◽  
Measurement Results ◽  
Processing Of Measurement Results ◽  
Measuring Force ◽  
Measuring Unit

An article devoted to the development of the latest equipment for testing road structures during the diagnostics of roads both in the process of repair and construction, and in the process of operation. A measuring station for stamp tests of road structures and their layers has been developed, which unites the test equipment into a single automated complex mounted on the base car. This eliminates the need for manual labor of the operator, increases productivity and accuracy of tests, provides the ability to perform multiple loads. At the same time, any truck or road vehicle can be used to create the load. A measuring unit with special software installed on it is used for registration and processing of measurement results. The results of laboratory tests of the measuring station, which were carried out in the laboratory of the department of metrological support of measurements of geometric quantities of SE «Ukrmetrteststandard» are highlighted. The obtained results indicate that the values of measuring force, absolute error and range of measurements of the station of movement of the station meet the regulatory requirements.

scholarly journals Heave Motion Measurement by Adaptive Filter Based on Longuet-Higgins Wave Model

2017 ◽  
Vol 2017 ◽  
pp. 1-8
Author(s):  
Jiazhen Lu ◽  
Qiuwei Luo ◽  
Yanqiang Yang
Keyword(s):  
Adaptive Filter ◽  
Cutoff Frequency ◽  
Wave Model ◽  
Absolute Error ◽  
Average Error ◽  
Measurement Results ◽  
Highpass Filter ◽  
Normal Method ◽  
Heave Motion ◽  
Rough Sea

A method is proposed to obtain heave motion information based on the Longuet-Higgins wave model. The Longuet-Higgins wave model which is closer to the sea wave is introduced. Based on it, random process of the noise is analyzed and the highpass filter is designed to reduce errors. Then it is the key point in this article that an adaptive algorithm is put forward because of the complexity of the waves. The algorithm adjusts the cutoff frequency to reduce the amplitude attenuation of the filter by analyzing the wave. For the same reason the comprehensive parameter of the phase compensation can be also obtained by the algorithm. Simulation measurement results show that under the rough sea situation the maximum value of absolute error is 0.4942 m according to the normal method, the method is 0.1170 m, and the average error ratio of the rough sea test reduces to 3.89% from 12.54%, which demonstrates that the adaptive filter is more effective in measuring heave movement. A variety of simulation cases show that the adaptive filter can also improve the precision of the heave motion under different sea situations.

scholarly journals Induction of Highly Dynamic Shock Waves in Machining Processes with Multiple Loads and Short Tool Impacts

2019 ◽  
Vol 9 (11) ◽  
pp. 2293 ◽  
Author(s):  
Andreas Tausendfreund ◽  
Dirk Stöbener ◽  
Andreas Fischer
Keyword(s):  
Shock Waves ◽  
High Speed ◽  
Short Pulse ◽  
Milling Process ◽  
Manufacturing Processes ◽  
Speckle Photography ◽  
Machining Processes ◽  
Initial State ◽  
Multiple Loads ◽  
Measurement Results

In order to study the mechanical loads of a workpiece in manufacturing processes such as single-tooth milling, in-process measurements of workpiece deformations are required. To enable the resolution of shock waves due to the mechanical impact of the tool, a novel measurement system based on speckle photography is introduced to measure the dynamic deformations and strains with a high temporal and spatial resolution. The measurement results indicate deformations and strains propagating through the workpiece with the speed of sound triggered by the tool impact (i.e., the tool impact is shown to induce shock waves during milling). Finite element simulations of the workpiece behavior are performed in addition, which support the experimental findings. In the considered case, the dynamic excitation subsides after 300 ms. Hence, in processes with even shorter cyclic multiple loads, the tool encounters an already excited initial state during machining, which needs to be taken into account when precisely modeling the milling process and the resulting workpiece quality. Finally, the measurement results demonstrate that speckle photography in combination with modern high-speed cameras and compact short-pulse lasers provides a deeper understanding of individual manufacturing processes.

scholarly journals Research of the probability of the "flip" of approximating function during the processing of measurement results

2019 ◽  
Vol 104 ◽  
pp. 02003
Author(s):  
Vladimir Marchuk ◽  
Dmitry Chernyshov ◽  
Ilya Sadrtdinov ◽  
Alexander Minaev
Keyword(s):  
Confidence Intervals ◽  
Additive Noise ◽  
A Priori ◽  
Rate Of Change ◽  
Statistical Characteristics ◽  
Sample Length ◽  
Signal Function ◽  
Measurement Results ◽  
Processing Of Measurement Results ◽  
A Priori Uncertainty

The paper presents the results of the studies of the probability of a “flip” of the approximating function when processing the measurement results under conditions of a priori uncertainty about the signal function and the statistical characteristics of additive noise. It is analytically proved that the confidence intervals of the probability of the absence and the presence of a “flip” are equal, which is confirmed by the experimental results. The dependences of the “flipping” of the approximating function on the sample length, the dispersion of additive noise and the rate of change of the function itself are obtained.

Design of Forming Shape Measurement System for Laser Molten Pool in Laser Fabricating

2010 ◽  
Vol 37-38 ◽  
pp. 327-330 ◽  
Author(s):  
Jian Bo Lei ◽  
Zhen Wang ◽  
Li Feng Liu
Keyword(s):  
Laser Cladding ◽  
Molten Pool ◽  
Detection System ◽  
Shape Measurement ◽  
Optical Elements ◽  
Shape Distribution ◽  
Special Software ◽  
Measurement Results ◽  
Destructive Measurement ◽  
Non Destructive

In order to study forming shape distribution of laser molten pool in laser fabricating, a CCD-based image detection system was developed. The system mainly consists of a CCD-based detector, optical elements, an image acquisition card and its special software. Experiments on shape measurement of the laser molten pool were carried out. It was shown that 2D morphology and the dimension of laser molten pool could be measured in real time. The (X, Y) dimension of the laser molten pool in laser cladding was (2.6 mm, 2.5 mm) with an approximately ellipsoidal shape. Laser cladding parameters were optimized according to the measurement results. It was a non-destructive measurement method, which would be a new method for online measurement and feedback control in laser fabricating.

MODELING OF STATIC CHARACTERISTICS OF PNEUMATIC STRAIN GAUGE TRANSDUCER

2019 ◽  
pp. 48-52
Author(s):  
A. P. Vasytenko ◽  
A. Yu. Tarakhovskiy
Keyword(s):  
Strain Gauge ◽  
Electrical Signal ◽  
Design Parameters ◽  
Measuring Instruments ◽  
Static Characteristics ◽  
Air Jet ◽  
Jet Impact ◽  
Measurement Results ◽  
Strain Gauge Transducer ◽  
Processing Of Measurement Results

Measuring instruments that implement the pneumatic principle of measurement, have a number of significant advantages: small dimensions of the measuring equipment, allowing to produce multiparameter control in a limited size of the working area, insensitivity to vibration, simplicity of design and reliability. The disadvantage of pneumatic converters is a discrete output electrical signal, which does not allow the processing of measurement results. In this regard, it seems appropriate to investigate the pneumatic-electric Converter, which includes a jet pneumatic and differential strain gauges, which allows to obtain an analog electrical signal at the output. The article describes the design and principle of operation pneumoenteritis Converter to control the diameter of the part. Pneumotensometric Converter converts the change in the diameter of the part in the movement of the nozzle, which causes a change in the force of the air jet on the beam, its deformation and, accordingly, a change in the resistance of he strain gauge. An expression describing the stoic characteristic of the transducer and allowing to determine the force of the air jet impact on the load cell from the gap between the nozzle and the beam, the air pressure and the nozzle diameter is given. The results of modeling the static characteristics of the Converter at different combinations of design parameters are given, the values of straight sections of characteristics and sensitivity are determined, their comparative evaluation is given.

Verification and Comparison of Two Tribodiagnostic Methods for Analyzing of the Worn out Oils in Service

2015 ◽  
Vol 669 ◽  
pp. 426-433
Author(s):  
Janka Mihalčová
Keyword(s):  
Internal Control ◽  
Internal Standard ◽  
Statistical Processing ◽  
Test Sample ◽  
Quality Parameters ◽  
Acid Number ◽  
Total Acid ◽  
Preparation Methods ◽  
Measurement Results ◽  
Processing Of Measurement Results

The paper deals with comparison and verification of two standard methods for measuring the total acid number of used oils. This is a tribodiagnostic method used to the detection of important quality parameters of oils in service, which determine the degradation of oil filling. This significantly affects the life cycle of oil and, consequently, the lubrication system. The methods for measuring aircraft motor and insulating oils are compared. The method procedures, preparation titration solutions, solvents, through the use of the test sample and electrodes to the accuracy of the measurement on the sample oils are compared. It compares the process of preparation methods of titrating solution, solvents, samples and fills through the use of electrodes to the accuracy of the measurement on the sample oils. From measurements of the samples accuracy and validity of both methods using statistical processing of measurement results is calculated. It utilizes internal control of measurements by means of an internal standard and also inter-laboratory comparison of measurement results.

Computer for statistical processing of measurement results

1971 ◽  
Vol 14 (6) ◽  
pp. 906-909
Author(s):  
V. I. Teverovskii ◽  
A. A. Ivlev ◽  
Yu. N. Snegireva
Keyword(s):  
Statistical Processing ◽  
Measurement Results ◽  
Processing Of Measurement Results

scholarly journals Method of Limiting Shaft Voltages in AC Electric Machines

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3326
Author(s):  
Sebastian Berhausen ◽  
Tomasz Jarek
Keyword(s):  
Laboratory Tests ◽  
Permanent Magnets ◽  
Load Condition ◽  
Synchronous Machine ◽  
Electric Machines ◽  
Electrical Machines ◽  
Voltage Measurement ◽  
Bearing Defects ◽  
Measurement Results ◽  
External Power

The article presents a new method of counteracting shaft voltages and currents in AC electrical machines. It is based on the use of an auxiliary winding located in the stator of the machine. The design of a test stand adapted to the measurement of shaft voltages of the machine, based on the prototype of a synchronous machine with permanent magnets, has been presented. The model was used to conduct a number of laboratory tests aimed at confirming the functionality of the auxiliary winding in various operating states of the machine (including no-load and load condition during generator operation). The article focuses on demonstrating the beneficial effect of the auxiliary winding on the level of induced shaft voltages in an electric machine. In order to confirm the close dependence of the circular flux in the stator yoke on the shaft voltage, shaft voltage measurement results for various cases of external power supply of auxiliary winding forcing a circular flux are presented. Regardless of the laboratory tests, a simulation model of a synchronous machine with permanent magnets, on which calculations were carried out to analyze the work of the auxiliary winding located in the stator yoke, was developed. The article is supplemented by a review of damage to electrical machines with a detailed description of bearing defects, as well as a brief de-scription of issues related to the mechanism of generating shaft voltages and currents in electrical machines and methods of counteracting them.

Sign in / Sign up

Export Citation Format

Share Document